PROJECT SUMMARY Needle electromyography (EMG) remains the standard approach for assessing neuromuscular disease. While the technique has proven to be clinically valuable over the last 80 years, it has important limitations. These include its not being sensitive to alterations in muscle composition and structure, its inability to assess the contractile apparatus of muscle, and its subjective nature with an inter-rater reliability of only 60% and a specificity for disease of only 70%. One technology that could be incorporated seamlessly into the EMG needle to overcome its limitations is electrical impedance myography (EIM). By combining EIM and EMG into a single needle device there is the potential for greatly enhancing the accuracy of EMG, the clinical standard, ultimately yielding a ?smarter EMG? technology to evaluate neuromuscular disorders. The development of this new ?smarter EMG? technology has been termed needle impedance-electromyography (I-EMG) and it is the main focus of Haystack Diagnostics, Inc., a small business concern based in Boston, MA. In Aim 1 of this Phase 1 SBIR application, Haystack Diagnostics, Inc., will perform finite element simulations to design different I-EMG needles topologies. These needles will be then manufactured on a fee-for-service basis by FHC, Inc., (Bowdoin, ME), a company with which we have previously worked with expertise in custom needle manufacture. In Aim 2, we will test the needle designs in phantom media (saline and agar) and in groups of healthy, wild-type mice and amyotrophic lateral sclerosis (ALS) mice. We will evaluate the EIM and EMG data both independently and together to identify the most effective and robust design, both in terms of repeatability and in differentiating healthy from diseased muscle, comparing to standard EMG as a reference. At the conclusion of this work, Haystack Diagnostics, Inc., will be well positioned to pursue a Phase 2 SBIR application seeking to develop and test I-EMG technology in patients with a variety of neuromuscular diseases, including ALS. With expressed interest from the medical community and Natus Medical, Inc., the world?s largest commercial EMG manufacturer, we believe that if successful, Haystack Diagnostics, Inc., technology could ultimately find wide application in clinical neuromuscular disease practice.